Twenty Two Dead, 59 Injured Following Explosion At Ariana Grande Concert In Manchester

Police have urged people to stay away from the area.

Twenty two people have been confirmed dead and 59 were injured following an explosion at an Ariana Grande concert in Manchester, England, which authorities are treating as a "possible terror incident".

Greater Manchester Police confirmed the fatalities at Manchester Arena, where thousands of people, including many children, were gathered for the pop singer's concert.

Twenty-two people were killed and 59 were injured when a lone bomber detonated an improvised explosive as the concert came to a close.

"We have been treating this as a terrorist incident and we believe that while the attack last night was conducted by one man, the priority is to establish whether he was acting alone or as part of a network," Chief constable Ian Hopkins said in a statement.

"The attacker, I can confirm, died at the arena. We believe the attacker was carrying an improvised explosive device, which he detonated, causing this atrocity."

Hopkins earlier said police are working closely with the national counter terrorism policing network and UK intelligence partners.

Dave Thompson via Getty Images
Injured concert-goers are treated by emergency services at Victoria Railway Station close to the Manchester Arena. The station has been evacuated following the explosion.

BBC Home Affairs Correspondent Daniel Sandford reported that senior national Counter-Terrorism officers are assembling in London.

Video has emerged on social media which appears to show the moment the explosion goes off, and the confusion and growing fear which followed:

The North West Ambulance Service confirmed that paramedics took 59 people from the arena to surrounding hospitals, in addition to treating a number of "walking wounded" at the scene. Police have confirmed that the injured are being treated at six hospitals across the Greater Manchester region.

Police were called to the arena at 10:33pm on Monday night (7:33am Tuesday AEST), just after Ariana Grande had finished performing.

Authorities have warned people to stay away from the area and have cordoned off the surrounding streets.

Police have been scouring the scene for any further explosive devices. Just before 2am local time, they set off a controlled explosion in Cathedral gardens following the discovery of a "suspicious item", but it turned out to be abandoned clothing.

British Prime Minister Theresa May said in a statement: "We are working to establish the full details of what is being treated by the police as an appalling terrorist attack."

"All our thoughts are with the victims and the families of those who have been affected."

The incident comes on the fourth anniversary of the brutal murder of British Fusilier Lee Rigby, who was run over with a car before being attacked with knives and a cleaver by Islamic extremists near the Royal Artillery Barracks in London.

A music label spokesperson for Grande told Reuters that the US singer is "okay" following the explosion.

American rapper BIA (real name Bianca Landrau), who was the opening act on the night, has also posted on social media, reassuring fans that she and her team are unharmed.